Metrics question
Facebook Ads dropped by 20%. Mark Zuckerberg calls you and asks you to fix it. What do you do?
- Meta
- Metrics
- Hard
Practice this question out loud. An AI interviewer asks it, follows up like a real interviewer would, and scores your answer. Type or speak.
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What this question tests
Ability to run a fast, structured root cause investigation under pressure with an executive stakeholder.
How to approach it
- Confirm the metric and timeframe precisely: which ads product, what region, and over what period the 20 percent drop happened.
- Rule out measurement issues first, such as a tracking or reporting pipeline bug, before assuming a real business drop.
- Segment the drop by advertiser type, geography, platform (Feed, Reels, Instagram) and auction dynamics to isolate where it is concentrated.
- Check for external causes: a policy change, iOS tracking changes, a major advertiser pausing spend, or a competitor's promotion.
- Check for internal causes: a recent algorithm change, an auction bug, or a UI change that hurt ad load.
- Communicate a short term mitigation and a timeline for root cause, rather than promising an instant fix to Zuckerberg.
What a strong answer includes
- Starts with 'is the data even right' before jumping to business explanations, which senior PMs do under pressure.
- Segments the drop instead of treating it as one uniform event, since a real 20 percent global drop is rare.
- Names a real precedent, e.g. iOS App Tracking Transparency's known impact on ad targeting and revenue.
- Separates immediate communication (what we know now) from root cause work (what we will know in 48 hours).
Common mistakes
- Jumping straight to a fix before confirming the number is accurate and understanding where the drop is concentrated.
- Giving Zuckerberg a guess dressed up as an answer instead of a structured investigation plan.
- Ignoring the possibility of a measurement or reporting bug entirely.
Likely follow-up questions
- What would you tell Zuckerberg in the first hour?
- How do you rule out a tracking or reporting bug?
- What would you check first, internal or external causes?
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More questions from Meta
Learn the skill behind it
Chapters of the AI PM course that teach what this question tests.
- Chapter 9: Prove it paid off: outcomes, economics, and pricing
- Chapter 2: Data fluency: SQL, logs, and reading the truth yourself
- Chapter 14: Get the job: the AI PM interview loop